Whisky has been produced in Japan since 1870, but it was not produced commercially until 1924, by the Yamazaki distillery. Japanese whisky emulates Scotch Whisky in most respects, and therefore is also spelled without the "e".
There are currently about 10 distilleries producing whisky in Japan, but the two most well known are Suntory and Nikka. Both produce blended as well as single malt whiskies.
One of the chief differences between the Japanese style of whisky and the Scottish, is their method of doing business.
The vast majority of Scotch sold in the world is blended, and Scottish distilleries typically focus their efforts on a single malt which is then sold to a blender who uses several whiskys to achieve the desired flavor profile. The Japanese are more reluctant to share products with competing distilleries and it has been argued that this lack of diversity has lessened the quality of Japanese blends.
Recently however, individual Japanese distilleries have begun producing a greater range of malts, thus achieving their blend profile without trading between other whisky makers. It is quite common for a single Japanese distillery to produce a wide range of styles, from the smokey and peaty style of Islay, through the heavily sherried, to the lighter and more delicate floral notes of Speyside.